I was out like a rock

This one was heard during a conversation about how everyone slept the night before. This is a congruent conflation of “out like a light” and “slept like a rock”, both meaning to get a deep and restful sleep. “Slept like a log” is probably the most common idiom for restful sleep, but “slept like a rock” is also acceptable, as is “top” and “baby” as well. See also https://malaphors.com/2020/02/24/you-were-out-like-a-log/. A big thanks to Joanne Grieme for hearing this one and passing it on.